Fluid couplers used in fluid transport applications are common and widely used. Typically, such connectors require proper dimensioning so that seal and/or assembled surfaces can be maintained to provide a no leak, no spill connector. These connectors also employ quick connect/disconnect features having manually operated latches for connecting other pieces of fluid dispensing equipment. Further, valve control parts and assemblies may be employed for controlling fluid flow. Such latch parts and assemblies are often disposed external the main flow bore or channel of the coupling body for user operation and accessibility.
U.S. Pat. Nos. 5,494,074 and 5,938,244 employ latch assemblies including multiple parts that reside out of the bore and on the outer surface of the coupling body. In order to protect these latch assembly parts, vertical sidewalls are formed as part of the main coupling body. To reduce costs, these couplers are formed as integrally molded parts, including such vertical sidewalls and other irregular, non-symmetric structures.
However, in forming these irregular structures on a coupling body, problems can occur in the dimensions of the inner bore and flow channel. In the molding process while transiting from thick to thin surfaces to provide for non-symmetric shapes, the flow channel dimensions, for instance, may become distorted. This distortion can occur due to the unpredictability of the resulting molded part, and can produce coupling body dimensions with inconsistent results. The unpredictability occurs when a molded part designed with inconsistent wall sections (combination of thick and thin wall sections) is injection molded and then allowed to cool post-mold. The plastic material shrinks as it cools and causes dimensional deformation, and may occasionally produce internal voids. Furthermore, different plastic materials may not have the same shrink characteristics.
While shrinkage is anticipated and accounted for in the build of a molding tool, the solution may not be as uniform or linear as engineering simulations and models suggest. Molding tools generally are built using an overall shrink compensation factor. An experienced tool builder can then make additional dimension modifications to the desired scale of the molding tool, and compensate for problems that the models do not predict. Further, post-mold shrinkage is not consistent from cycle to cycle, and sometimes the part-to-part differences can be dramatic. Such problems can be further aggravated by asymmetric parts or parts having thick wall sections or sharp corners.
For coupling bodies that require tight, specific dimensions and that undergo this distortion, the sealing and/or assembled surfaces inside the bore may be compromised. Typically, this distortion can make it necessary to go back and fine-tune the coupling body part back to specification requirements.
While the above devices are suitable for their purposes, there is a need for an improved coupler device including a soft overmold portion that provides the non-symmetrical structure needed to protect and cover any parts outwardly extending from the coupling body. Further, a coupling device is needed where the coupling body avoids dimension distortion and where sealing surfaces and other assembled surfaces are preserved. A connector is desired that provides a design suitable for quick connect/disconnect couplers, while being produced with lower cost and higher efficiency.